Faba bean is the leading in area coverage and total production of pulses in Ethiopia. However, soil acidity becomes the major production limiting factor of faba bean in the highlands of Ethiopia. Information on genetic variability and heritability of faba bean genotypes on different traits under soil acidity stress is scanty. Thus, this study was conducted to estimate genetic variability of faba bean genotypes on grain yield and related traits at soil of pH 4.66, 4.96 and 4.49 at Holetta, Watebecha Minjaro and Jeldu, respectively, during 2017 main cropping season. The experiment comprised 50 faba bean genotypes arranged in randomized complete block design with three replications. Data were collected on grain yield (g/5plants) and some other agronomic traits: days to 50% flowering, days to 90% maturity, grain filling period, plant height (cm), number of poding nodes/plant, number of pods/ poding node, number of pods/plant, chocolate spot disease (%) and 100-seeds weight (g). Analysis of variance for traits studied showed significant differences among genotypes, locations and their interaction (P ≤ 0.01) for all traits except number of pods/poding node for the interaction. Computed genotypic (GCV) and phenotypic coefficient of variation (PCV) values were ranged from 1.08-23.05 and 1.20-23.26%, respectively, whereas heritability (H2) and genetic advance as percent of the mean (GAM) ranged from 24.63 -98.22% and 2.0 - 47.13%, respectively. The highest values for all components were recorded for 100-seeds weight while lowest values except for H2 computed for days to 90% maturity. The observed PCV and GCV values were high for 100-seed weight and moderate for grain yield, number of poding node/plant and pod/plant. The values of PCV were higher than GCV for all traits. Hence, the high variation between PCV and GCV (6.78) for chocolate spot was due to environmental stress (soil acidity) besides the genetic constitution of tested genotypes. High H2 and GAM were observed for 100-seeds weight, number of pod/plant and poding node/plant. Traits with high H2 indicated that selection based on mean would be successful in improving the traits. Therefore, selection based on phenotypic performance of genotypes would be effective to improve traits that have high GAM coupled with high H2 estimates.